As per email with Ward:  Replaced K(W) with k W^(alpha-1), so  K(W) W  is replaced by  k W^alpha.  This is part of the Manning-Weisbach form in Schoof, but only beta=2 case.  Verification results identical because k=K_0,alpha=1.  Nbreen results very similar with k=1.0e-3 and alpha=2.0.  Observe that with alpha>1 we have a degenerate diffusion so that water doesn't spread out so much (e.g. far under non-melting base); I think this is good.